• Geomechanics and Engineering
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• v.10 no.6
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• pp.737-755
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• 2016

The load transfer depth of a ground anchor is the minimum length required to transfer the initial prestressing to the grout column through the bonded part. A thorough understanding of the mechanism of load transfer as well as accurate prediction of the load transfer depth are essential for designing an anchorage that has an adequate factor of safety and satisfies implicit economic criteria. In the current research, experimental and numerical studies were conducted to investigate the load transfer mechanism of ground anchors based on a series of laboratory and field load tests. Optical FBG sensors embedded in the central king cable of a seven-wire strand were successfully employed to monitor the changes in tensile force and its distribution along the tendons. Moreover, results from laboratory and in-situ pullout tests were compared with those from equivalent case studies simulated using the finite difference method in the FLAC 3D program. All the results obtained from the two proposed methods were remarkably consistent with respect to the load increments. They were similar not only in trend but also in magnitude and showed more consistency at higher pullout loading stages, especially the final loading stage. Furthermore, the estimated load transfer depth demonstrated a pronounced dependency on the surrounding ground condition, being shorter in hard ground conditions and longer in weaker ones. Finally, considering the safety factor and cost-effective design, the required bonded length of a ground anchor was formulated in terms of the load transfer depth.

• Journal of the Korean GEO-environmental Society
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• v.2 no.4
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• pp.51-61
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• 2001

A series of model tests and analyses by load transfer function were performed to study load-settlement behaviour with relative compaction ratio of soil and embeded depth of pile. In the model tests, embeded depth ratio(L/D) of pile were installed 15, 20, 25 and relative compaction of soil(RC) is 85%, 95% and then cement were injected at around perimeter of pile. For analysis of embedded pile, the paper were compared results of model tests with analysis results by Vijayvergiya model and Castelli model, Gwizdala model of elastic plasticity-perfect plastic model and then the fitness load transfer mechanism was proposed to predict load-settlement behaviour of embeded pile. The analysis results of predicted bearing capacity by load transfer function, ultimate bearing capacity of embeded pile were approached to measured value and behaviour of initial load-settlement curve were estimated that load transfer function by Castelli were similar to measured value. The result of axial load analysis of bored pile shows that skin friction estimated by load transfer mechanism is investigated more a little than that of measured values.

• Journal of the Korean Solar Energy Society
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• v.25 no.3
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• pp.1-9
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• 2005

The purpose of this paper was to analyze the influence of radiation and convection component separated from surface heat combined transfer coefficient on dynamic Heat load simulation. In general, it was not considered the mutual radiation of walls that heat load simulation calculated by surface combined heat transfer coefficient. In order to solve this problem, we had developed new simulation program to calculate radiation heat transfer and convection heat transfer respectively, and verified the influence of radiation component with this new program, in indoor heat transfer process.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1188-1194
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• 2008

As computation technologies has developed, the analysis using load transfer is mainly performed. But most of the functions used in the above program has been developed in foreign countries. Also in our nation, lots of studies concerning load transfer are being researched. The investigation of suitability about the piles installed in our grounds, however, is required as functions acquired experientially, basing on the piles installed in foreign grounds. In this background, the load transfer curve required to use load transfer method on its design through the analysis of field tests inside our nation intends to be made, on which this research focuses.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.539-550
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• 2009

As computation technologies has developed, the analysis using load transfer is mainly performed. But most of the functions used in the above program has been developed in foreign countries. Also in our nation, lots of studies concerning load transfer are being researched. The investigation of suitability about the piles installed in our grounds, however, is required as functions acquired experientially, basing on the piles installed in foreign grounds. In this background, the load transfer curve required to use load transfer method on its design through the analysis of field tests inside our nation intends to be made, on which this research focuses.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.760-766
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• 2008

As computation technologies has developed, the analysis using load transfer is mainly performed. But most of the functions used in the above program has been developed in foreign countries. Also in our nation, lots of studies concerning load transfer are being researched. The investigation of suitability about the piles installed in our grounds, however, is required as functions acquired experientially, basing on the piles installed in foreign grounds. In this background, the load transfer curve required to use load transfer method on its design through the analysis of field tests inside our nation intends to be made, on which this research focuses.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.1008-1015
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• 2010

Discharged pollution load is varied as rainfall changes in the area with combined sewer system. Changes in discharged pollution load are directly related with those of sewer transfer flow. Therefore, it is important to identify the pattern of sewer transfer flow for the analysis of changes in discharged pollution load. This study reviewed the type of distribution of sewer transfer flow for 17 sewage treatment plants and developed simple formular to estimate sewer transfer flow as rainfall changes. 11 facilities showed to have some relation with rainfall in the change of sewer transfer flow but 6 facilities to have no relation. Relationships between rainfall amount and sewer transfer flow showed that 6 facilities out of 11 had relatively strong relationships above R2=0.5, which were considered to be affected directly by rainfall changes. The formular which explain the relationship between rainfall and sewer transfer flow can be applied in the analysis of rainfall effects on discharged pollution load, therefore, the more appropriate evaluation will be done.

• Journal of Power Electronics
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• v.16 no.1
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• pp.102-110
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• 2016

Contactless power transfer technology is gaining increasing attention in city transportation applications because of its high mobility and flexibility in charging and its commensurate power level with conductive power transfer method. In this study, an inductively coupled contactless charging system for a 48 V light electric vehicle is proposed. Although this study does not focus on system efficiency, the generic problems in an inductively coupled contactless power transfer system without ferromagnetic structure are discussed. An active load matching method is also proposed to control the power transfer on the receiving side through a load matching converter. Small signal modeling and linear control technology are applied to the load matching converter for port voltage regulation, which effectively controls the power flow into the load. A prototype is built, and experiments are conducted to reveal the intrinsic characteristics of a series-series resonant inductive power charger in terms of frequency, air gap length, power flow control, coil misalignment, and efficiency issues.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.3
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• pp.203-211
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• 2001

This paper presents load transfer efficiency of skewed transverse joint of jointed concrete pavement with the fatigue model test. A 1/12 scale model was used to satisfy the geometry, loading, material similitude, which are variables to the skew angel of transverse joint. As the test results by fatigue load 700kgf applied, the deflection and stress of transverse joint were decreased as to increasing of skew angle of transverse joint. In addition, load transfer efficiency of transverse joint with skew angle is better than the load transfer efficiency of transverse joint without skew angle.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.2
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• pp.179-188
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• 1994

This paper deals with implementation of an expert system to obtain an optimal plan of load transfer for fault restoration with the capability of security monitoring and assessment in distribution systems. Based on the technique of load transfer tree analysis, the proposed expert system can afford to assist system operators in proposing an optimal plan of load transfer for fault restoration, In paticular, an application of the proposed ES to practical distribution systems yields an optimal load transfer plan which ensures system security by considering security assessment for contingency of feeders and main transformers in the knowledge based sense.